The present invention is concerned with a tomography imaging system, preferably a CT device, which comprises an acquisition unit, a patient positioning table with a horizontally movable patient board or plate, which patient board can be slid through a scan region of the acquisition unit for examination, and a first support device which is arranged with regard to the patient positioning table to support the patient board upon passing through the scan region.
Technology of tomography imaging systems, in particular of computer tomography devices, is generally known. These are described in portions of books by H. Morneburg, “Bildgebende Systeme für die medizinsche Diagnostik”, ISBN 3-89578-002-0 (1995), pp. 429–466 and by W. Kalender, “Computertomographie”, ISBN 3-89578-082-0 (2000), pp. 17–34.
Patient positioning systems used in connection with tomography imaging systems are known in the patent literature, for example, see U.S. Pat. No. 6,668,403 B2, whose disclosure is incorporated herein by reference thereto, and U.S. Patent Application Publication No. US 2002/0104163 A1, whose disclosure is incorporated herein by reference thereto, and which claims priority from German 101 03 331.1. In this printed application, a tomography imaging system is disclosed with a patient positioning table with a horizontally movable patient board or plate, which, for additional support of the extending patient board, has, on the side of the acquisition unit opposite the patient positioning table, an additional (as the case may be) height-adjustable support that is positioned separately from the acquisition unit and that should support the patient board in the extended state.
Because of the support of the patient board with the height-adjustable support, it is now possible to move along the scan path or even provide a full-body or whole-body scan.
A disadvantage with this known tomography imaging system is that the height-adjustable support should be arranged at a sufficient distance from the acquisition unit in order to not prevent the tilting of the acquisition unit before or between the scans. However, if the distance of the height-adjustable support to the acquisition unit is selected too large, the range in which the patient board is not supported is also too large. A deflection or warpage of the patient board will occur given an incumbent patient. The deflection of the patient board and the imprecise patient position will result and have a negative influence on the measurements. It would namely be conceivable to prevent the deflections of the patient board by increasing the rigidity of the board, for example by use of stiffening materials; however, the material absorption behavior given the use of additional material also negatively affects the measurements of the device.
The known tomography imaging system is moreover not particularly comfortable with regard to the positioning of the patient. The patient to be examined should always be inserted into the opening of the acquisition unit in the same position in order to ensure the reproducibility of the examination results and the exactitude of the image representation. For this, a certain positioning effort is necessary in the known tomography imaging system. The patient board must be aligned with regard to the acquisition unit and, at the same time, the height-adjustable support must be moved so that the patient board is not tilted upward or downward. There are, thus, three units to be positioned, namely the patient board with the patient, the acquisition unit and the height-adjustable support.
Another disadvantage of this known tomography imaging system exists in the additional space requirement for the height-adjustable support. There is, thus, a space requirement on one side of the acquisition unit for the positioning device for the patient positioning table with a horizontally movable patient board and on the other side of the acquisition unit, additional space is necessary for the height-adjustable support. Overall, the measurement arrangement of the tomography imaging system with the necessary peripheral devices is very long along the movement direction of the patient board, so that a correspondingly large measurement space must also be available.